C3900-universalk9-mz.spa.157-3.m8.bin: [upd]

Once the router restarts, verify the active version using show version . Lifecycle and Support Considerations

: Indicates the feature set. This is a "Universal" image containing all Cisco IOS features. Strong cryptographic features (VPN, SSH, HTTPS) are enabled by default under the k9 designation. You unlock advanced features like Security, Unified Communications, or Data using Cisco Software Activation Licenses. C3900-universalk9-mz.spa.157-3.m8.bin

Optimized for the Cisco 3900 series hardware, such as the Cisco 3945/K9 router . Once the router restarts, verify the active version